Page 417 of 1767
13 CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select ªCKPS×RPM (TDC)º in ªDATA MONITORº mode with CONSULT-II.
3. Read idle speed.
SEF817Y750 25 rpm
Without CONSULT-II
1. Start engine and let it idle.
2. Check idle speed.
750 25 rpm
OK or NG
OKEINSPECTION END
NGEReplace electronic control fuel injection pump.
TROUBLE DIAGNOSIS Ð BASIC INSPECTIONZD30DDTi
Basic Inspection (Cont'd)
EC-55
Page 418 of 1767

Symptom Matrix Chart
SYSTEM Ð Basic engine control sys-
temSYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
Electronic control fuel injection pump
mainframe4444444445534 Ð *1
Injection nozzle33333333344 3EC-24 *2
Glow system1111EC-239
Engine body3333333 344 3 EMsection *3
EGR system3 3 EC-222
Air cleaner and ducts 3 3 MA section *4
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*1: Fuel injection system malfunction or fuel injection timing control system malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
EC-56
Page 419 of 1767

SYSTEM Ð Basic engine control sys-
temSYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator lamp illuminates.
Can be detected by CONSULT-II?
Fuel cutBLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
Electronic control fuel injection pump
mainframe443 4 54 333 Ð *1
Injection nozzle 3 3 4 EC-24 *2
Glow system 1 EC-239
Engine body 3 3 3 3 3 3 EM section *3
EGR system 3 EC-222
Air cleaner and ducts 3 3 MA section *4
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*1: Fuel injection system malfunction or fuel injection timing control system malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
Symptom Matrix Chart (Cont'd)
EC-57
Page 420 of 1767
SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
ENGINE CONTROL
Electronic control fuel injection pump
circuit*a, *b 1 1
111111111
Ð
*c, *d
Mass air flow sensor circuit*a, *c
111
EC-88
*b
Engine coolant temperature sensor
circuit*a, *b 1 1 1 1 EC-95 *1
Vehicle speed sensor circuit *a, *b 1 EC-99
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*1: Compensation according to engine coolant temperature does not function.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
Symptom Matrix Chart (Cont'd)
EC-58
Page 421 of 1767
SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator lamp illuminates.
Can be detected by CONSULT-II?
Fuel cutBLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
ENGINE CONTROL
Electronic control fuel injection pump
circuit*a, *b 1
111
Ð
*c, *d 1
Mass air flow sensor circuit*a, *c
1 EC-88
*b 1
Engine coolant temperature sensor
circuit*a, *b 1 1 1 1 EC-95 *1
Vehicle speed sensor circuit *a, *b 1 EC-99
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*1: Compensation according to engine coolant temperature does not function.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
Symptom Matrix Chart (Cont'd)
EC-59
Page 422 of 1767

SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
ENGINE CONTROL
Accelerator switch (FC) circuit*a, *b 1
EC-104
*c
Fuel cut system line*a, *c
EC-232
*b 1 1 1 1 *2
Accelerator position sensor circuit *a, *b 1 1 1 EC-130
Crankshaft position sensor (TDC)
circuit*a, *b
EC-145
*d 1 1
Charge air pressure sensor circuit*a,
*b, *c1 1 EC-215
Swirl control valve control solenoid
valve circuit*a, *b
EC-263
*c 1111
Variable nozzle turbocharger control
solenoid valve circuit*a, *b 1 1
EC-281
*c 1 1
Intake air control valve control sole-
noid valve circuit*c 11111111EC-273
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*2: Engine runs on after turning ignition switch OFF.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
Symptom Matrix Chart (Cont'd)
EC-60
Page 423 of 1767

SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator lamp illuminates.
Can be detected by CONSULT-II?
Fuel cutBLACK SMOKE
WHITE SMOKEWarranty symptom code AG AH AJ AK AL AM AP HA
ENGINE CONTROL
Accelerator switch (FC) circuit*a, *b
1 1 EC-104
*c
Fuel cut system line*a, *c 1 1
EC-232
*b 1 *2
Accelerator position sensor circuit *a, *b 1 1 EC-130
Crankshaft position sensor (TDC) cir-
cuit*a, *b 1 1
1 1 EC-145
*d
Charge air pressure sensor circuit *a, *b, *c 1 1 EC-215
Swirl control valve control solenoid
valve circuit*a, *b 1
EC-263
*c 1 1 1
Variable nozzle turbocharger control
solenoid valve circuit*a, *b 1 1
EC-281
*c 1 1
Intake air control valve control sole-
noid valve circuit*c EC-273
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*2: Engine runs on after turning ignition switch OFF.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
Symptom Matrix Chart (Cont'd)
EC-61
Page 424 of 1767

SYSTEM Ð ENGINE CONTROL system
Malfunction
SYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART
(EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATINGWarranty symptom code AA AB AC AD AE AF
ENGINE CONTROL
Start signal circuit *a, *b 1 1 EC-248 *3
PNP switch circuit*a, *b 1
EC-251
*c
Accelerator position switch (Idle) cir-
cuit*a, *c 1 1 1
EC-130
*b 1 1 1 *4
Accelerator position switch (Full) cir-
cuit*a, *b 1 1 1 EC-130
Ignition switch circuit*a 1 111
EC-79
*b*5
Power supply for ECM circuit*a
EC-79
*b
1 - 5: The numbers refer to the order of inspection.
(continued on next page)
*a: Open
*b: Short
*c: Ground short
*d: Noise
*3: Start control does not function.
*4: Accelerator position sensor NG signal is output.
*5: Engine does not stop.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONZD30DDTi
Symptom Matrix Chart (Cont'd)
EC-62